Waterproof concrete floor for bridges.



A.v H. RHETT. wATrnoorhrooNcETr. moon ron BRIDGES. APPLIGATIQN FILED 0012-8, 1913.

Patented Feb. 9. 1915.

,UNITED STATES PATENT OFFICE.,

ALBERT RHETT, OF NEW YORK, N. Y.

` vini'1i.-:ni. 1zoor CONCRETE ArLooR FOREEIDGES.

such structures, when they 'are built over streets or passageways, to render them water-proof, so that rain-water which may fall upon the bridge or viaductwill not drip down to the street or passage' below. Fur-kl thermore, it is desirable in these structures to prevent water fromentering the abutting surfaces between the frame structures and the body or bodies of concrete which they sustain. f l

The type ofbridge which I especially have in mind'to, improve; comprises, usually, sets" of'longitudinal girders connected together by ,flooring Yconsisting 'of cross supports embedded in or supporting asolid concrete lo'o'rl` It is a. comparatively simple matter to Vreni-ier thetop surface of this concrete ooringwaterlproof, butl the vertical joints between thejconc'rete body andthe longitudinal,y girders present considerable diflii culty, due tothe -fact that the movements of th'elivelofad upon the bridge and variations injtefmperaturef'cause kthe 'joint at this location'jtofopen and close, sov that during a rain storm, water is permitted to pass `downward between the abuttingr surfaces of the girders and 'the concrete bed and drip to the pasl' tiiines lexcludewaterfrom this joint and tosageway below, or,y sometimes freeze in the jo,int,caulsing rupture ofthe cement bed.

`fl`heref re the object of my invention is to provide ai'construction which will at all thfat endl myinvention consists in interposingrr between the abuttingsu'r'fa ces of the c oncrete bed and its supporting girders, a filling or :course of elastic, coherenti'and `adherent nateriall which isi-preferably located 1n the angle' between' the upper surface of the concrete bed andthe vertical surface of the web Y of the gir-der, which material; by reason of its 'adhering quality, will remain 'attached to both of the abutting surfaces, and by reason of its coherentquality will inalntainits own integrity, and by reason of its elasticity Specification of Letters Patent. Application led October 8,l 1913. Serial No. 793,977.

Patented Feb. 9, 1915v will yield to permit of the'relativemove i A of the half-through solid type, but it is not my intention to be limited to thisv specific form, as the invention is capable of broad application with all types'o' bridges and viaducts constructed with concrete ioors `and metallic supporting structures.

In the accompanying drawing the figure is a fragmentary cross-sectional view through a multi-track bridge having a concrete floor showing 'my improved waterproof joint and membrane for the floor.

The main girders or supporting structure for the bridge are constructed in the usual `manner and consist of webs 1 to which are fastened the top and bottom plates 2 of the girders by angle plates 3, the girders being provided with stifl'ener angles l of the usual construction. Arranged transversely to the main girders and supported thereby, are cross-beams 5, one of which is shown in dotted lines. supported by these transverse girders 5 which are embedded therein, the floor forming with the webs 1 of the main girders a joint 7. The top surface of the Hoor 6 may be graded from the sides to the center, forming a. central longitudinal depression ofsuficient depth and width. to receive the track ballast 8 on which the tires 9 and the rails 10 rest. The concrete door ,6 maybe reinforced in any desired manner to prevent it from cracking under the strains resulting from the live load or the expansion and contraction of the concrete due to temperature changes. I

rvPreferably at the upper end of the joint 7 a. recess or trench 11 is formed in theconcrete Hoor 6, which. recess is preferablycut-:in the concrete before ithasirrnly, set. This recess or trench is filled with an elastic, adhesive, cohesive non-hardening compound 12 which adheres to both the metallic surface The concrete floor or deck 6 isv lll ofthe web of the girder and the surface of the concrete body to form with each of these an absolutelyl Water-'tight ioint. Compoundsl having. rubber or gutta 'percha as a base have given the best results, but any compound which complies with the above stated requirements may -be used.

When the concrete floor is subjected to the recurrent weight of passing trains or to chan es of temperature, the recess 11 and' witha thin layer 13 of the same com-pound as the filler 12 which is joined 4thereto and forms therewith a water-proof .covering eX- tending over the entire top surface of the concrete Hoor, from web to web, which will eii'e'ctually Qrevent any water from leaking through. Preferably the layer 13 and the .filler 1'2. are covered with burlap .or some other fabric, over which is placed a concrete layer 14 which shields the same .from contact with the track'ballast .8.

While trenches only betweenthe webs of the main girders and the concrete ioor yet .it is to be understood that these r cesses are cut adjacent the sti'fener angles, brackets, and,

in fact, all supporting structures which- .form joints with the concrete floor and-1n .which the intervening space between it fand- ,the concrete is subject to variation due to the deformation of the concrete Hoor.A

While it ispreferable to form the iecess '11 for the filler 12 at the same time that the bridge is constructed, yet it is evident thatgmy invention 1s capable of use withl bridges already built, in which the concrete has `-pulled away from the supporting structure to form a gap or crevice, which gap with or without additional shaping may be filledl with a compound such as I have de-A scribed. v Having ldescribed' m claim 1.`In a bridge construction, a concrete floor, a horizontal metal girder to which said' fioor'is joined and forming a support thereforasaid floor being in contact only invention, I

with substantially the lower half of the web, pf girder and said ioor and girderA I have kshown the recesses or,

being separated -at the top of their vertical llne of jointure by an intervening spacean adheslve, elastic Waterproof filler inasaid space -forminga water-tight joint with the glrder and floor respectively, a layer of the same compound over the top surface of the floor and joined to said filler to forni a water-proof coveringfor said bridge and protective covering of concrete over said leren 2. A half through girder bridge comprislng main longitudinal, vertically disposed, Webbed, metal girders, -cross beams supported thereby, a concrete floor supported by said beams and in ycontact only with substantially the lower halves of said webs, a water excluding body of elastic, coherent and adherent material interposed in the' joint between the abutting surfaces ol' said weband' Hoor and spread over said fioor in a continuous layer,I anda protective layer; of concrete covering said last na'med layer and adapted to receive the track and ballast. 3'. In -a bridge construction, a concrete floor, a horizontal girder to which said floor is joined and forming a support therefor, said floor being in contact only with substantially the lower half of the web of said girder and said fioor and girder bein separated at the top of the vertical line-o jointure by an intervening space` and an :1dhesive, elastic water-proof filler in said space forming a water-tight joint with `the girder and floor, respectively, and a layer of water-proofing'material over the top surface of the floor and joined to the filler to form therewith a .water-proof co"ering over the entire fioor of-the bridge and a protective covering of concrete over said layer.

4:. A half through girder bridge comprising main longitudinal, vertically` disposed, webbed, metal girders, cross beams.l

supported thereby, a concrete floor supported by said beams and in contact only with substantially the lower halves of said webs, a water excludingbody of elastic,

coherent and adherent material interposed,l

in the joint between the abutting surfaces of said web and floor, a layer of water-` proofing material over said fioor and connecting said materia; interposed in the joint formed therewith. a continuous water-proof Alayer over said Hoor. and a protective: layer of concrete covering over said last named layer and adapted to receive the track and ballast.

In 'witness whereof., I subscribe my signature, in the presence of two witnesses.

ALBERT H. RHETT.

Witnesses:

WALDo M. CHAPIN, JULE ZELENxo. 

